select * from two tables with different # of columns - php

How would I select different columns from two different tables, such as:
SELECT username, email FROM `table1`
UNION
SELECT * FROM `table2` WHERE username = 'user1';
I'm getting an error "#1222 - The used SELECT statements have a different number of columns". From what I understand UNION will not work,
Is there a way to accomplish this, since I would need unequal number of columns and rows and there are no mutual/similar entries in the two tables (i.e. user1 is not listed in table1)?
Can this not be done in one query?
thank you!

You can fake the missing columns using an alias - e.g.
SELECT username, email, '' as name FROM `table1`
UNION
SELECT username, email, name FROM `table2`
WHERE username = 'user1';
where name is in table2, but not in table1
Unless you're confusing UNIONS with JOINS:
SELECT table1.*, table2.* FROM
table1 INNER JOIN table2
ON table1.username = table2.username
this would merge both tables, so you get all the columns on the same row.

If there's no mutual or similar entries in the two tables, these should be two different select statements.
SELECT username, email FROM `table1`;
SELECT * FROM `table2` WHERE username = 'user1';
What's your motivation for doing otherwise?
Are the entries in table2 related to table1? Would a join be more appropriate?
SELECT t1.username, t1.email, t2.*
FROM table1 t1
JOIN table2 t2 ON t1.username = t2.username
WHERE t1.username = 'user1';

In the table with less columns, try
SELECT *, 0 as col1, 0 as col2, ...
etc in order to make them the same number of columns.

Related

compare two table with row and column

I have two tables table1 and table2
In table1 fieldname is cert_no and in table2 fieldname is cer1,cert2,cert3,cert4,cert5
The value which was not in table2 (cer1,cert2,cert3,cert4,cert5) alone want to display
If both table has same value only transfile_file want to display
SELECT *
FROM table1
WHERE folio = '123456'
AND cm_flag !='X'
AND certificate_no NOT IN
(SELECT CONCAT(certno1,certno2,certno3,certno4,certno5,certno6,certno7,certno8,certno9,certno10)
FROM table2
WHERE tofolio = '123456'
)
If you use for example Microsoft SQL Server there is a function EXCEPT that return the different rows between 2 tables with the same fileds (same name, same types and same positions). In Oracle there is MINUS operation that is the same of EXCEPT.
In MySQL does not implement a EXCEPT or MINUS operation which is a unfortunate as it can allow for better execution plans in some cases than the alternatives.
This is a valid aternative and more performing than use NOT IN operation: realize a join is the best solution in SQL.
enter code here
SELECT a.*
FROM table1 as a
LEFT JOIN table2 as b
ON a.tofolio = b.tofolio
WHERE b.tofolio IS NULL
Try:
SELECT * FROM table1 WHERE folio = '123456' AND cm_flag !='X' AND certificate_no NOT IN (SELECT CONCAT(certno1,',',certno2,',',certno3,',',certno4,',',certno5,',',certno6,',',certno7,',',certno8,',',certno9,',',certno10) FROM table2 WHERE tofolio = '123456')

Search in two mysql tables with non identical tables (keyword search)

I want to make my keyword search in two mysql tables. my tables don't have any identical column names. But I tried few queries, they didn't work for me.
Keyword IS 07731A0328
I tried this:
$sql = "select a.*, b.* from table1 a inner join table2 b on a.col1=b.htno WHERE a.col1 like '$name'";
$sql = "select a.*, b.* from table1 a join table2 b on a.col1=b.htno WHERE a.col1 like $name";
Can someone help me with this? Thank you!
TABLE 1
TABLE2
Join is your friend:
http://www.w3schools.com/sql/sql_join.asp
Combine rows from two or more tables, based on a common field between them.
SELECT * FROM TABLE1 INNER JOIN TABLE2 ON TABLE1.col1=TABLE2.htnon
WHERE TABLE1.col1 = "07731A0328"
The query will be
SELECT * FROM Table1,Table2
WHERE Table1.col1=Table2.htnon AND Table1.col1 = "07731A0328"

PHP SQL Query Fields from Another Table Join

I am trying to get a query using fields from 2 tables.
I need to query Table1 but only Table2 has the variable venue_location that I need to query.
Basically I need to count all records on Table1 where Table1.venue_location = $MyVariable.
Here is what I've put together but I believe I need to use Joins for this?
Table1
- venue_id
Table2
- venue_id,
- venue_location
SELECT * FROM Table1 WHERE table1.venue_id = table2.venue_id and table2.location = '$MyVariable'
How can I do a query for this?
Use the power of join table
SELECT * FROM Table1
JOIN Table2 USING(venue_id)
WHERE table2.location = '$MyVariable'
You can get back the count of rows with mysqli_num_rows() in PHP, or change le select by SELECT COUNT(*) AS nbRow FROM ... and check of value in nbRow column
You can join two tables on venue_id and then group it by venue_id where location is your $MyVariable.
Your final query will look like:
SELECT count(table2.venue_id)
FROM Table1
JOIN Table2 ON table1.venue_id = table2.venue_id
WHERE table2.location = '$MyVariable'
GROUP BY table2.venue_id
try this
SELECT Table1.venue_id, Table2.venue_location FROM Table1 INNER JOIN Table2
ON Table1.venue_id='$MyVariable';

Select unmatched records from two tables of MYSQL

I have two tables Table1 and Table2 with some records
id is the common column in both tables and primarykey is set to this column in table1
There are many records in table1 and some of these records (not all) are updated into table2.
Now I want retrieve from table1 the records not updated into the table2.
For example in table1 there are records 1,2,3,4,5,6,7,8,9
And in table2 there are 3,4,7,9
Now How can I retrieve these records form table1 1,2,5,6 those not updated into table2
I wrote this query :
SELECT Table1.id, Table1.DATE, Table1.C_NAME, Table1.B_NAME
FROM [Table1] INNER JOIN Table2 ON Table1.SLIPNO <>Table2.id;
But the expected result not coming. This query lists all the records repeating each one record manytimes
Can any body give me solution to get the expected result.
select *
from table1
where table1.slip_no NOT IN (select id from table2)
Assuming name of common column is id
Or you can modify your query as
SELECT distinct (Table1.id, Table1.DATE, Table1.C_NAME, Table1.B_NAME)
FROM [Table1]
INNER JOIN Table2 ON Table1.SLIPNO <>Table2.id
A good reference on SQL joins
SELECT t1.*
FROM table1 AS t1
LEFT OUTER JOIN table2 AS t2 USING(id)
WHERE
t2.id IS NULL;
You can use the NOT IN operator on a subquery for table2.
Alternatively, use MINUS with two regular queries listing the ids in each table:
SELECT id FROM table1
MINUS
SELECT id FROM table2;
Try this
SELECT Table1.id, Table1.DATE, Table1.C_NAME, Table1.B_NAME FROM [Table1]
WHERE
NOT EXISTS (SELECT * from Table2 WHERE Table1.SLIPNO !=Table2.id );
You can use the following query
SELECT id FROM database1.table WHERE id NOT IN(SELECT id FROM database2.table)
SELECT child_table.id FROM child_table LEFT JOIN parent_table ON child_table.parent_id = parent_table.id WHERE parent_table.id IS NULL
This left join query returns all the records of the child_table when there is no match in the parent_table. When there is no match, all parent_table fields will be NULL.
inner join will not help. To get unmatched records I tried this:
SELECT
A.ID,A.DATE,A.NAME
FROM TABLE1 A
WHERE CONCAT(A.ID , A.DATE ,A.NAME)
NOT IN
(SELECT CONCAT(B.ID , B.DATE ,B.NAME) as X
from TABLE2 B) ;

How do I compare two tables data?

Hi I do have an old table and new table with same index/data. TABLE1 and TABLE2
but TABLE1 has got more data than TABLE2. this was maintained by some one and I dont know how this happened. so my question is how do I compare these two table and find which data is TABLE2 missing?? there is almost 200000 datas there so manually doing is not possible...
in PHP:
http://us.php.net/manual/en/function.array-diff.php
in SQL:
SELECT * FROM TABLE1 WHERE id {NOT} IN ( SELECT id FROM TABLE2 )
depending on criteria of comparison
Solution without nested query:
select TABLE1.id from TABLE1 left join TABLE2 on TABLE1.id = TABLE2.id where TABLE2.id is null
Did you mean something like this:
SELECT * FROM TABLE1 t1 WHERE NOT EXISTS(SELECT * FROM TABLE2 WHERE t1.id == t2.id)
By same index I am hoping you mean they share a primary key?
SELECT * FROM TABLE1 WHERE username NOT IN (SELECT username FROM TABLE2)

Categories